Yayu Agustini, Rika, Liska Mutiara Septiana, and Aliya Azkia Zahra. “Chemical Characteristics of Ultisols and Purple Eggplant Yields Due to the Application of Composted Paper Sludge and NPK Fertilizer”. Jurnal Ilmu Pertanian Indonesia 31, no. 3 (May 27, 2026): 579–586. Accessed June 5, 2026. https://journal.ipb.ac.id/JIPI/article/view/69980.